1. Field of the Invention
This invention relates generally to a system and method for optimizing wireless vehicle to vehicle communications and, more particularly, to a system and method configured to maximize the amount of data that can be transferred from one vehicle to another during a transient encounter by adaptively adjusting the message packet size and data communication rate during an inter-vehicle communication session.
2. Discussion of the Related Art
Traffic accidents and roadway congestion are significant problems for vehicle travel. Vehicular ad-hoc network based active control and driver assistance systems allow a short-range wireless vehicle communications system, such as a dedicated short range communication (DSRC) system or a WiFi-based wireless communication system, known to those skilled in the art, to transmit messages to other vehicles. DSRC or WiFi can be used to implement wireless-based vehicle features that can improve driver convenience, roadway efficiency, and facilitate many types of in-vehicle services. The DSRC technology enables a new class of vehicle features based on communication with other vehicles (“V2V”) or the infrastructure (“V2I”). Broadly, the term “V2X” can be used to signify the various types of communication applications that are enabled by DSRC or WiFi in vehicular environments.
Vehicle-to-vehicle (V2V) and vehicle-to-infrastructure (V2I) applications require a minimum of one entity to send information to another entity. For example, many vehicle-to-vehicle applications can be executed on one vehicle by simply receiving broadcast messages from a neighboring vehicle. These broadcast messages are not directed to any specific vehicle, but are meant to be shared with a vehicle population. In these types of applications where collision avoidance is desirable, as two or more vehicles communicate to each other and a collision becomes probable, the vehicle systems can warn the vehicle drivers, or possibly take evasive action for the driver, such as applying the brakes. Likewise, traffic control units can observe the broadcast of information from passing vehicles and generate statistics on traffic flow through a given intersection or roadway.
In addition to providing advance notification of roadway events, DSRC or WiFi can also be used to exchange other types of information between vehicles (V2V) or between vehicles and roadway infrastructure (V2I). In such cases, vehicles could potentially download large amounts of data from another vehicle or from an infrastructure access point. Since vehicles are highly mobile, they will have limited opportunities to perform data transfer operations since the time period in which they are within communication range is likely to be limited. In an extreme case, two vehicles may pass each in the opposite direction while traveling at highway speeds. Given the limited encounter duration, it will be important to optimize the data throughput during the time window in which communication is possible.
Therefore, what is needed is a system and method to maximize the amount of data that can be transferred from one vehicle to another during a transient encounter.